I just cant figure it out

[hardkoratvmxr]

I have a 300ex and cant figure out why it isnt running right. When I first start it it runs like a champ but when it warms up at full throttle it acts like the choke is on. I have fresh gas in it and the main jet is not clogged. I had a buddy say it is the valves but i am not sure that is it. But like i said it runs awesome the first 15-20 minutes i ride. after that it acts like the choke is on at full throttle.

[400exrider707]

Jetting perhaps? Whats the plug look like? Could also be an electrical problem. Not a whole lot of information to go on here.

[bwamos]

Clean your Reverse and Neutral indicator switch connectors next to your rear brake pedal, under the sheet metal cover.

If they arent making a good connection it tells your CDI that you are in reverse (even when you are not) and your limiter will be dropped down to like 4000rpms. Be sure to clean them with contact cleaner, then use some dielectric grease to waterproof the connection.